This application claims the priority of PCT International No. PCT/EP99/08438 filed in Europe on Nov. 4, 1999 and, German Patent Document filed in Germany on Nov. 14, 1998, the disclosures of which are expressly incorporated by reference herein.
The present invention relates to a convertible top for an automobile, and more particularly to a convertible top which is adjustable between a closed position and a folded-down position, comprising a convertible-top mechanism, a convertible-top fabric supported by the convertible-top mechanism, a side bar of the convertible-top mechanism which comprises two limbs arranged at an angle, of which one limb is vertical in the closed position in the side region of the convertible-top mechanism, is held pivotably of a joint arranged on a vehicle body, and has a first axis and a second axis running at an angle to the first axis, in which, in the folded-down position, one limb of the side bar runs transversely with respect to the longitudinal direction of the vehicle, and that end side of the limb which is remote from the joint faces toward that side region of the convertible-top mechanism which lies opposite the joint.
DE-C 943 747 has discloses an automobile convertible top which can be adjusted between a closed position, in which the vehicle interior is closed off, and a folded-down position. The automobile convertible top includes a convertible-top fabric which is held taut on a convertible-top mechanism which comprises a plurality of transverse and side bars. The side bars are of two-part configuration, having a first bar part, which is bent into the form of part of a circle, is held on a joint and is mounted so that it can rotate about two axes, and a second, horizontal bar part, which adjoins the first bar part via a rotary joint. In the closed position, the two bar parts span a side window. The second, horizontal bar part is connected to a front roof bar which is used to produce the connection to the window frame of the windshield.
To open the known convertible top, the bent part of the bar is pivoted about its two axes, and in the folded-down position the bent part of the bar lies transversely with respect to the longitudinal direction of the vehicle and faces in the direction of the opposite side of the convertible top. At the same time, the horizontal part of the bar is rotated through approximately 180xc2x0, about its joint axis, relative to the first bar part, so that in the folded-down position that end side of the horizontal bar part which is remote from the joint and is connected to the front roof bar is oriented oppositely to the bent part of the bar.
In the front section of the convertible top, the convertible-top fabric can only be attached to the horizontal bar part and to the front roof bar. On account of the bar being angled twice in the folded-down position, it is not possible for the convertible-top fabric also to be attached to the bent part of the bar which spans the rear side edge of the side window. Otherwise, the fabric, on account of the angled folded-down position of the bars, would undergo excessive stretching and damage the material. The fabric can only be attached to the front mechanism of the convertible topxe2x80x94the roof bar and the horizontal bar part which spans the top edge of the side window. By contrast, in the region of the bent part of the bar, it is impossible to provide a fixed connection with the fabric material, and this has an adverse effect on the seal in the transition from the bent part of the bar to the side edge of the side window.
The sealing problem is intensified further by the fact that, between the edge of the window and the side bar, the seal is divided into two parts, one for the upper edge and one for the side edge, and that in the region of adjacent end sides of the seal there is a risk of the sealing action being lost.
Another adjustable convertible top for a vehicle has been described in DE 196 46 035 A1. The convertible top has a pivotable side bar which engages partially around a side window of the vehicle and is held in such a manner that it can pivot about a horizontal transverse axis running transversely with respect to the longitudinal axis of the vehicle. During the transfer movement from the closed position into the folded-down position, the side bar describes part of a circle, and in the folded-down position the bar extends a relatively long way back toward the trunk, a fact which has to be correspondingly taken into account when dimensioning the compartment.
An object of the present invention is to improve the seal of a convertible top in the region of the side windows.
According to the invention, this object has been achieved by providing that the pivotable side bar a single-part component, and the horizontal limb of the side bar, in the closed position of the convertible top, extends as far as a window frame of the windshield and is held directly on the window frame.
The two limbs of the pivotable side bar, in particular a horizontal limb and a bent limb, form a single-part component, with the result that the number of degrees of freedom is reduced and possible sources of problems are eliminated. With this configuration, only one bar of the convertible-top mechanism need engage over both the rear edge and the upper edge of a side window, so that it is possible to produce a continuous, uninterrupted seal between window and side bar. The seal is attached to the side bar. Aging phenomena in the sealing material or temperature fluctuations have a considerably reduced effect on the seal provided in the convertible top according to the invention, because there are no joints in the transition between the side edge and the upper edge of the side window.
The seal is also improved by connecting the fabric material to the side bar over the entire length of the latter, so that in the closed position of the convertible top the fabric material is held securely on the side bar both at the rear edge and at the upper edge of the side window. There is virtually no possibility of the fabric material distorting, which in the closed position may lead to leaks.
A further advantage is that unforeseeable and unexpected creasing in the fabric material during opening of the convertible top no longer occurs, at least to a reduced extent, because the fabric is attached to the convertible-top mechanism over a greater length compared to the prior art. Thereby, possible uncontrollable movements of the fabric are restricted. When it is being moved from the closed position into the folded-down position, the fabric material is always gathered up in the intended way, thus preventing undesirable kinks and increasing the service life of the convertible top.
In an expedient variant, the length of the horizontal limb of the side bar is no longer than half the width of the compartment into which the convertible top is lowered in the folded-down position. This has the advantage that the two side bars which span opposite side windows in the closed position can be stowed with end sides facing toward one another in the compartment without impeding one another. As a result, the side bars can be configured mirror-symmetrically with identical kinematics on both sides of the convertible top, thus simplifying the configuration. A further advantage is that the convertible top takes up less space in the folded-down position, so that the compartment can be of smaller dimensions and more space is available for the trunk.
According to a currently preferred embodiment, the side bar is connected to a transversely running roof frame of the convertible-top mechanism, which frame, in the closed position, is held on the window frame of the windshield. The roof frame may be of multipart configuration, in particular in three parts, with one central and two side sections. The side sections are held on the central section of foldable joints, and the side bars are connected to the side sections. In the closed position, all sections of the roof frame are folded open in a row, corresponding to the shape of the window frame of the windshield, and form a load-bearing, inherently stable, generally arc-shaped bar. In the folded-down position, the side sections are folded together about the axis of their joints, resulting in a compact stowed arrangement.
According to another currently preferred embodiment, the front roof frame can be eliminated by producing the connection between the window frame of the windshield and the convertible top, in the closed position, exclusively by way of the side bars, which also provide the required transverse tensioning of the fabric material. This configuration is distinguished by being of very low-weight and also taking up a very small amount of space in the folded-down position.